The invention relates to an arrangement for controlling a motor vehicle friction clutch which is operated by an actuating drive.
Proposed in the not pre-published German Patent Application P 38 23 387 applied for on July 7, 1988 is an arrangement which facilitates parking of a motor vehicle equipped with an automated friction clutch. In normal running, the automated friction clutch is automatically engaged and/or disengaged when starting up and changing gear, as the case may be. During manoeuvring, for example when parking, however, the friction clutch should only be partially closed so that the vehicle moves at a creep speed with a slipping clutch. According to the earlier patent application, this is achieved in that the accelerator pedal which controls an output adjusting means on the internal combustion engine of the motor vehicle, for example its throttle valve or injection pump, does not influence the load adjusting means during a limited initial travel of the pedal which follows on from the inoperative position of the accelerator pedal. A pedal position sensor ascertains the position of the accelerator pedal at any given moment, at least within this initial pedal travel and generates a pedal position signal which adjusts the actuating drive of the friction clutch via a control so that it assumes a clutch position between the completely disengaged position and the completely engaged position of the friction clutch. The clutch position and thus the torque transmitted by the friction clutch can thus be controlled by the accelerator pedal within its initial travel.
Between the pedal position on the one hand and the torque transmitted by the friction clutch on the other, there should be a predetermined for example directly proportional relationship which ought not to alter during the period of use of the motor vehicle but which is dependent upon a number of influencing variables, particularly the condition of the friction clutch, such as for example its temperature or its state of wear and tear.